[Easy signin] Wire up userClick auth attempt to easy unlock app and back

chrome/browser/signin/easy_unlock_auth_attempt.cc

+// Copyright 2014 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "chrome/browser/signin/easy_unlock_auth_attempt.h"
+
+#include "base/logging.h"
+#include "chrome/browser/extensions/api/screenlock_private/screenlock_private_api.h"
+#include "chrome/browser/profiles/profile.h"
+#include "chrome/browser/signin/screenlock_bridge.h"
+#include "crypto/encryptor.h"
+#include "crypto/symmetric_key.h"
+
+
+#if defined(OS_CHROMEOS)
+#include "chrome/browser/chromeos/login/easy_unlock/easy_unlock_key_manager.h"
+#endif
+
+namespace {
+
+// Fake secret used to force invalid login.
+const char kStubSecret[] = "\xFF\x00";
+
+// Decrypts the secret that should be used to login from |wrapped_secret| using
+// raw AES key |raw_key|.
+// In a case of error, an empty string is returned.
+std::string UnwrapSecret(const std::string& wrapped_secret,
+                         const std::string& raw_key) {
+  if (raw_key.empty())
+    return std::string();
+
+  // Import the key structure.
+  scoped_ptr<crypto::SymmetricKey> key(
+     crypto::SymmetricKey::Import(crypto::SymmetricKey::AES, raw_key));
+
+  if (!key)
+    return std::string();
+
+  std::string iv(raw_key.size(), ' ');
+  crypto::Encryptor encryptor;
+  if (!encryptor.Init(key.get(), crypto::Encryptor::CBC, iv))
+    return std::string();
+
+  std::string secret;
+  if (!encryptor.Decrypt(wrapped_secret, &secret))
+    return std::string();
+
+  return secret;
+}
+
+}  // namespace
+
+EasyUnlockAuthAttempt::EasyUnlockAuthAttempt(Profile* profile,
+                                             const std::string& user_id,
+                                             Type type)
+    : profile_(profile),
+      state_(STATE_IDLE),
+      user_id_(user_id),
+      type_(type) {
+}
+
+EasyUnlockAuthAttempt::~EasyUnlockAuthAttempt() {
+  if (state_ == STATE_RUNNING)
+    Cancel(user_id_);
+}
+
+bool EasyUnlockAuthAttempt::Start(const std::string& user_id) {
+  DCHECK(state_ == STATE_IDLE);
+
+  if (!ScreenlockBridge::Get()->IsLocked())
+    return false;
+
+  if (user_id != user_id_) {
+    Cancel(user_id);
+    return false;
+  }
+
+  ScreenlockBridge::LockHandler::AuthType auth_type =
+      ScreenlockBridge::Get()->lock_handler()->GetAuthType(user_id);
+
+  if (auth_type != ScreenlockBridge::LockHandler::USER_CLICK) {
+    Cancel(user_id);
+    return false;
+  }
+
+  state_ = STATE_RUNNING;
+
+  // TODO(tbarzic): Replace this with an easyUnlockPrivate event that will
+  // report more context to the app (e.g. user id, whether the attempt is for
+  // signin or unlock).
+  extensions::ScreenlockPrivateEventRouter* router =
+      extensions::ScreenlockPrivateEventRouter::GetFactoryInstance()->Get(
+          profile_);
+  return router->OnAuthAttempted(auth_type, "");
+}
+
+void EasyUnlockAuthAttempt::FinalizeUnlock(const std::string& user_id,
+                                           bool success) {
+  if (state_ != STATE_RUNNING || user_id != user_id_)
+    return;
+
+  if (type_ != TYPE_UNLOCK) {
+    Cancel(user_id_);
+    return;
+  }
+
+  if (!ScreenlockBridge::Get()->IsLocked())
+    return;
+
+  if (success) {
+    ScreenlockBridge::Get()->lock_handler()->Unlock(user_id_);
+  } else {
+    ScreenlockBridge::Get()->lock_handler()->EnableInput();
+  }
+
+  state_ = STATE_DONE;
+}
+
+void EasyUnlockAuthAttempt::FinalizeSignin(const std::string& user_id,
+                                           const std::string& wrapped_secret,
+                                           const std::string& raw_session_key) {
+  if (state_ != STATE_RUNNING || user_id != user_id_)
+    return;
+
+  if (type_ != TYPE_SIGNIN) {
+    Cancel(user_id_);
+    return;
+  }
+
+  if (!ScreenlockBridge::Get()->IsLocked())
+    return;
+
+
+  std::string unwrapped_secret = UnwrapSecret(wrapped_secret, raw_session_key);
+
+  // If secret is not set, set it to an arbitrary value, otherwise there will
+  // be no authenitcation attempt and the ui will get stuck.
+  // TODO(tbarzic): Find a better way to handle this case.
+  if (unwrapped_secret.empty())
+    unwrapped_secret = kStubSecret;
+
+  std::string key_label;
+#if defined(OS_CHROMEOS)
+  key_label = chromeos::EasyUnlockKeyManager::GetKeyLabel(0u);
+#endif  // defined(OS_CHROMEOS)
+
+  ScreenlockBridge::Get()->lock_handler()->AttemptEasySignin(
+      user_id,
+      unwrapped_secret,
+      key_label);
+  state_ = STATE_DONE;
+}
+
+void EasyUnlockAuthAttempt::Cancel(const std::string& user_id) {
+  if (type_ == TYPE_UNLOCK)
+    FinalizeUnlock(user_id, false);
+  else
+    FinalizeSignin(user_id, "", "");
+  state_ = STATE_DONE;
+}